SaveFileDialog.Filter
using System; using System.Windows.Forms; class MainClass { static void Main(string[] args) { SaveFileDialog dlg = new SaveFileDialog(); dlg.Filter = "RichText Files (*.rtf)|*.RTF|Text Files (*.txt)|*.TXT" + "|All files (*.*)|*.*"; if (dlg.ShowDialog() == DialogResult.OK) { Console.WriteLine(dlg.FileName); } } }